彩色CCD成像法测量光污染

Color CCD Imaging Method for Measuring Light Pollution

光环境是城市人居条件的一项重要内容,光污染的监测主要是针对光环境。将色彩校正的方法应用于彩色CCD测量光环境亮度分布,并结合计算机图像处理技术,对不同的颜色转换矩阵进行实验分析,使得亮度计算值和实测值很好地吻合,得出图像RGB三刺激值与目标亮度的函数关系式。通过实验,对相机测量值与亮度计实测值进行对比,分析镜头渐晕现象对测量精度的影响,从而证实了此方法具有较高的测量精度。通过在不同亮度条件下对相机进行多次标定,提高了相机的亮度测量范围,以适应光环境测量的要求,此方法将在城市光污染的测量与防治领域具有很好的应用前景。

Light environment is very important to urban people＇ s habitation environment, and the measurement of light environment helps us to monitor the light pollution. Firstly, the color calibration method was applied to the color CCD camera for measuring the luminance distribution of light environment, different color transformation matrices was analyzed by using the computer image processing technology, the results showed that the luminance values measured by the camera matched with the luminance meter each other, and the digital image RGB tristimulus values had a formula relation with the target luminance. After that, an experiment was designed to compare the values measured by the camera with the luminance meter, another one was designed to analyze the effects of lens vignetting on measurement accuracy, these experiments confirmed that this method had high measurement accuracy. Finally, in order to enlarge the measurement range of luminance and adapt the requirement of light environment measurement, the camera was calibrated several times under different lighting conditions, and there will be a good prospect for this method＇ s application in the field of urban light pollution measurement and prevention.